{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T13:40:38Z","timestamp":1792590038817,"version":"4.5.0"},"reference-count":37,"publisher":"AIP Publishing","issue":"10","funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62201348"],"award-info":[{"award-number":["62201348"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shanghai Pujiang Program","award":["24PJD074"],"award-info":[{"award-number":["24PJD074"]}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,10,1]]},"abstract":"<jats:p>Electrical impedance tomography (EIT) relies on a controlled ac excitation current, while the effective load of a multiplexed instrument varies with electrode switching, contact impedance, excitation frequency, and object conductivity. This work develops a Howland current source module with auxiliary buffering and compensation feedback for EIT instrumentation. The architecture retains the main Howland current setting loop while adding a voltage follower and a dedicated compensation branch that acts on an internal node coupled to the output path rather than directly sensing the external load terminal. The module was characterized against a conventional single op amp Howland circuit in terms of frequency-dependent current accuracy, resistive load sensitivity, output signal-to-noise ratio (SNR), and estimated effective output impedance and was integrated into a 16-electrode EIT instrument for water tank validation. In the frequency sweep, at 100\u00a0kHz with a 5 k\u03a9 load, the proposed module delivered 0.4935 mA RMS with an error of \u22121.30%, compared with 0.3768 mA RMS and \u221224.64% for the conventional circuit. Over a 1\u20135 k\u03a9 load sweep at 100\u00a0kHz, the current variation decreased from 44.23% to 10.90%. At 100\u00a0kHz with a 3 k\u03a9 load, the output SNR increased from 30.0 to 41.2 dB, while the estimated effective output impedance increased from 15.4 to 31.7 k\u03a9. Water tank experiments with conductive, insulating, and mixed targets further demonstrated end-to-end operation within the complete EIT measurement chain. Overall, the results demonstrate improved excitation performance and practical system level integration for EIT instrumentation.<\/jats:p>","DOI":"10.1063\/5.0352997","type":"journal-article","created":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T12:54:07Z","timestamp":1792587247000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["A Howland current source module with auxiliary buffering and compensation feedback for electrical impedance tomography"],"prefix":"10.1063","volume":"97","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-2693-4105","authenticated-orcid":false,"given":"Yuewei","family":"Jiang","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering, University of Shanghai for Science and Technology , Shanghai 200093,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3457-0833","authenticated-orcid":false,"given":"Jianqing","family":"Jiang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, University of Shanghai for Science and Technology , Shanghai 200093,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"Li","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, University of Shanghai for Science and Technology , Shanghai 200093,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2768-1726","authenticated-orcid":false,"given":"Zeying","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, University of Shanghai for Science and Technology , Shanghai 200093,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2026,10,21]]},"reference":[{"key":"2026102108540365000_c1","doi-asserted-by":"publisher","first-page":"380","DOI":"10.1109\/OJCAS.2021.3075302","article-title":"Electrical impedance tomography for biomedical applications: Circuits and systems review","volume":"2","year":"2021","journal-title":"IEEE Open J. 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